Direct vent fireplace assembly

ABSTRACT

A fireplace assembly including a direct-vent combustion system which includes an air inlet, an air outlet each sealed from the other. It includes a pre-combustion chamber for entry of a primary fuel and air mixture, a burner unit, the burner unit comprising a burner, a base plate with metered holes or slots configured to allow control of the placement, volume and flow of air flowing from the air inlet into a mixing combustion chamber from the burner unit, and an ember bed located around the burner configured to create the mixing combustion chamber in the burner unit to enhance desired flame presentation by controlling mixing of incoming air with the primary fuel and air mixture.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional application Ser. No. 62/638,790 filed Mar. 5, 2018. The provisional is incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable.

BACKGROUND OF THE INVENTION

The subject matter herein relates generally to a portable direct vent assembly. More specifically, it relates to a secondary air/fuel mixing chamber and air directing channels to make burning characteristics, that while giving a realistic dancing yellow flame and glow of a wood fire, combine to give the unprecedented clean burn of a “vent free” product.

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

A direct vent fireplace is a generally prefabricated metal fireplace that employs a plurality, usually two, ducts in a direct-vent combustion system. “Direct vent” refers to a sealed-combustion system in which air for combustion is drawn from the outdoors through one duct, and waste combustion gases are exhausted to the outdoors through another duct.

Such fireplaces also include a combustion chamber in which fuel is mixed with air and is heated. Room air is generally drawn into the front of the fireplace from below the chamber and is heated, rises above the chamber, and exhausts at the front. An array of artificial logs are placed within the chamber, so that when mixed with propane or natural gas, simulates the aesthetics of actual burning logs. A vent cap at the exterior of the building closes off the hot gases exiting and diffuses the gases by a baffle.

BRIEF SUMMARY OF THE INVENTION

A direct vent fireplace assembly is provided that utilizes ceramic fiber and metal and other features described herein to create a chamber to mix and direct secondary air with a premixed primary gas/air mixture at the burner surface. This enhances speed of the flame to yellow and increases flame length, all while needing less btu's than traditional decorative flame fireplaces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of the direct vent assembly

FIG. 2 is schematic of the secondary mixing chamber

Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The following detailed description illustrates the claimed invention by way of example and not by way of limitation. The description clearly enables one skilled in the art to make and use the invention, describes several embodiments, adaptations, variations, alternatives, and uses of the claimed invention, including what is presently believed to be the best mode of carrying out the claimed invention. Additionally, it is to be understood that the claimed invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The claimed invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

As shown in FIGS. 1-2, the direct vent fireplace assembly 10 is designed specifically to address the above-mentioned considerations.

Venting is achieved through a direct vent system. The system connects to an air box 3 that continues to keep the exhaust and incoming air separate. The air box 3 and inlet pipe 37 delivers cool air from the room or outside through ducts 5 which lie below the burner 7 in a separate chamber 9.

There can also be a control 20 for the exhaust or incoming air that is controllable by a unit's user after installation. This helps create a customizable look of the flame produced based on the user's preferences in the various installations, altitudes and vent runs and plays into the effort in balancing the flow.

Under the burner 7, in an embodiment, air enters through a back wall 11 of the unit below a base plate 19; the base plate 19 is angled for log and ember bed presentation. This space also houses a primary air box 15 and shutters 17 that, through wire and tube connection, allow for the adjustment of primary air to the outside of the sealed combustion chamber without leakage.

In the above embodiment, the base plate 19 has precisely metered holes/slots 21 that control placement and the flow and amount of air into the combustion chamber. The primary air box 15 controls the air going to the burners, for primary gas air mix, allowing the installer to adjust this amount for a given application while the fire is burning.

After the air flows through the base plate 19, it comes up around the burner 7 and also can in a few other areas that provide the oxygen to precise areas in the combustion chamber.

While the base plate 19 controls relative amounts and placement of air, the ember beds 23 create a mixing chamber around the burner tubes 25 to enhance flame height by controlling mixing of the incoming air with the premixed gas air mixture of the burner tube 25.

The burner tube 25 has targets for mixing and is ported to put the gas air mixture in the burner 7 to desired locations. The ember bed 23 combines with the burner tube 25 to create a mixing combustion chamber 27 resulting in targeted air flow in precise volume, velocity and location, both in height and horizontally along the burner tube.

In an embodiment, the mixing combustion chamber 27 is constructed to have the appearance of, e.g., burnt logs, a charcoal bed, and brick made out of fiber and, in the cases of more contemporary looks, may be metal, porcelainized metal, glass or other materials. This allows for the flame to interplay with items in the mixing combustion chamber 27, such as the above-noted air flow directing features, allowing the flames to flow through the log design. This creates a unique appearance to the flame by altering its perceived depth.

Above the chamber 27 is a baffle 31 that controls the exhaust flow and exit locations 33. This enhances the flame appearance and quality of combustion in several ways. Exhaust exits 33 may be placed with great care and planning, thus precisely metering the exhaust exit. It further helps direct the flame by moving the exit location. This also aids in adjusting the size and visual speed of the flame.

The above combination of features thereby creates a desired flame presentation, a sculpted flame shape with a lively, high, quickly yellowing flame, and/or a reduced tendency to stretch over time.

A catalyst 35 is utilized in embodiments of the invention to decrease emissions to the point where the emissions from the entire assembly is similar to vent free alternatives.

Also provided is a method of heating or providing a decorative flame using a direct event fireplace assembly as described herein.

In view of the above, it will be seen that the several objects and advantages of the present invention have been achieved and other advantageous results have been obtained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 

What is claimed is:
 1. A fireplace assembly comprising: A fireplace unit comprising: A direct-vent combustion system comprising an air inlet and an air outlet or exhaust for waste combustion gases, wherein the inlet and outlet are sealed off from each other, A pre-combustion chamber for entry of a primary fuel and air mixture; A burner unit, the burner unit comprising a burner, a base plate with metered holes or slots configured to allow control of the place, volume and flow of air flowing from the air inlet into a mixing combustion chamber from the burner unit, and An ember bed located around the burner configured to create the mixing combustion chamber in the burner unit to enhance desired flame presentation by controlling mixing of incoming air with the primary fuel and air mixture.
 2. The fireplace assembly of claim 1 wherein the base plate is configured to meter secondary air into the chamber around the burner by which a desired flame presentation, sculpted flame shape, a lively, high, quickly yellowing flame, and/or reduced tendency to stretch over time.
 3. The fireplace assembly of claim 1 further comprising a controller for customization of the look, height, flame color and other characteristics by the user of the fireplace assembly.
 4. The fireplace assembly of claim 1 wherein the base plate is angled for log and ember bed presentation.
 5. The fireplace assembly of claim 1 wherein the base plate with metered holes or slots allows for targeting air flow in precise volumes, velocity and locations both in height and horizontally along the burner.
 6. The fireplace assembly of claim 1 wherein the ember bed is selected from a group comprising one or more of artificial burnt logs, charcoal beds and fiber constructed bricks.
 7. The fireplace assembly of claim 1 wherein the ember bed comprises a material made from one or more of metal, porcelainized metal, glass and cast ceramic fiber.
 8. The fireplace assembly of claim 1 wherein the fireplace unit further comprises a catalyst for passage through of the exhaust air prior to its leaving the fireplace unit.
 9. A method of heating or providing a decorative flame comprising: Igniting a fireplace assembly comprising: A fireplace unit comprising: A direct-vent combustion system comprising an air inlet and an air outlet or exhaust for waste combustion gases, wherein the inlet and outlet are sealed off from each other, A pre-combustion chamber for entry of a primary fuel and air mixture; A burner unit, the burner unit comprising a burner, a base plate with metered holes or slots configured to allow control of the place, volume and flow of air flowing from the air inlet into a mixing combustion chamber from the burner unit, and An ember bed located around the burner configured to create the mixing combustion chamber in the burner unit wherein a desired flame presentation is enhanced by controlling mixing of incoming air with the primary fuel and air mixture.
 10. The method of claim 9 wherein a user of the fireplace assembly by use of a controller, customizes the look, height, flame color and placement of flame's appearing in the fireplace assembly.
 11. The method of claim 9 wherein the method further comprises the step of installing the fireplace assembly of claim
 9. 